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In this paper, the discharge of an experimental ice-storage tank is analyzed. The storage tank is an internal melt-ice-on-coil system. The discharge process has been studied for different mass flow rates and supply temperatures in the range from 10ºC to 15ºC. The results indicate that once the ice breaks and floats towards the top of the tank, convection in the ice/water mixture is enhanced and the heat transfer fluid in the top coils becomes colder than in the bottom coils. Thus, an increase of the cooling power is generally observed around the ice-breaking point. Two correlations have been developed to reproduce the effect of the mass flow rate and supply temperature on the discharge duration and the mean cooling power. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 Keywords: Thermal storage, experimental installation, PCM, ice melting, ice floating *Manuscript-UnmarkedCopy Click here to view linked References

This paper presents the results of an experimental installation with an internal melt-ice-on-coil tank which has a total capacity of 172 kWh. The aim of this work is to analyse the freezing process in a tank with counter-current spiralshaped coils immersed in around 1855l water. An experimental campaign has been performed with different inlet temperatures and mass flow rates of the heat transfer fluid. This study analyses (i) the chiller performance, (ii) the iceformation process and (iii) the energy consumption of the installation. Supply temperatures between-2.5ºC and-5.2ºC have been sufficient to charge the tank without using any nucleating agents. The lowest energy consumption has been achieved for the fastest charging tests.

This paper aims to develop a dynamic model of the charging process of a commercial ice-storage tank. Firstly, three different 1 st order and 2 nd order numerical schemes have been compared to solve the transport equation of the heat transfer fluid. Euler's method has finally been chosen as the mass flow rate can vary throughout the charging and it avoids the oscillations which are introduced by Lax-Wendroff's and MacCormack's method. Secondly, the heat transfer outside the coils is analyzed. The numerical complications involved in the creation of the first ice layer around the tubes are discussed and an electrical resistance model is introduced to avoid this problem. The model results have provided a very good agreement with experimental measurements of charging tests which have been performed on a CALMAC ICEBANK tank with a capacity of 172 kWh. The model helps to predict the final part of the latent heat transfer process, where the thermal power is decreased due to the contact between the ice layers around adjacent tubes of the tank. Greek lettersHTF density (kg/m 3 )